Download problem

I have failed on two successive days to install Anki from the internet. Upon trying to open anki.2.1.33-mac.dmg (that I successfully downloaded), I am am given a message that the “Resource is not available.” Recommendations?

Tried restarting your computer?

Tried that. When trying to open the .dmg file the error message still said “Resource busy”.

It sounds like a macOS bug - maybe one of the search results here will help: